You guys know I have some pretty strong views about textual criticism. After all, I've written the DEFINITIVE 79-page book on the subject. (Oh my.)
This means that there are more important textual variants in Mark's Gospel relative to total verses than any of the other Gospels. But obviously they are not all viable.
A -- or maybe even the -- classic example? Mark 1:41. Here we are presented with two options. Either Jesus was "moved with compassion" when he healed the leper, or he was "moved with anger." In my opinion, there is no possible way the reading "moved with anger" can be original when you take the external evidence into account. The reading "moved with compassion" is contained in ALL of the majuscules (save one), ALL of the minuscules, ALL of the lectionaries, and ALL of the versions (except for 4 Old Latin witnesses). I think it's worth mentioning that I'm not the first to point this out. See this essay for a defense of "moved with compassion" on both external and internal grounds.
As you know, in the book I'm writing on New Testament interpretation, I have an entire chapter on textual criticism. You can't avoid this topic. I'm also really excited about a classic work on the subject that is about to be reprinted. I can't share the details yet, but look for an announcement very soon. Again, this isn't a subject just for experts. It affects all Christ's followers who want to live by God's word. So we must resist quick assumptions and settle into a long-term approach, which means leaning into the ABCs of the subject. It just makes sense.